Braving a court ban, 14 home improvement stores in France opened to the public Sunday in an increasingly bitter tug of war with the government over a law prohibiting trading on the traditional day of rest.

The move comes amid intense debate over France's labour practices. The government is seeking to continue a long tradition ruling out Sunday and late-night work, but at a time of record high unemployment, many employees regard the ban as antiquated.

Last week, both Leroy Merlin and Castorama, two home improvement chains, were ordered by a court to stop opening their stores in the Paris area on Sundays or face a fine of 120,000 euros ($162,000) per shop and per day.

But on Sunday, they opened anyway amid anger among employees and customers....